1. Field of the Invention
This invention relates to adjustable length planks that may be extended across trestles or the like to provide elevated support platforms.
2. Description of the Prior Art
Scaffolds and other forms of elevated platforms, usually of a temporary nature, are extensively used by workmen to provide support for performing work on elevated structures. Typically, such platforms include planks that extend between trestles or other vertical support members. Historically, wooden boards have served as such planks, but this practice has been greatly diminished because of federal and state occupational safety regulations. Thus, metal planks have extensively replaced the use of wood planks.
While use of metal can provide stronger, safer planks than wood, weight then becomes a problem so planks made of metal must be designed to provide maximum support strength with minimum weight. Also, in view of cost considerations, metal planks can not be discarded on site at the completion of a work project, as often was done with wood planks, so planks made of metal must be designed to assist in their transportation from one site to another, e.g., made adjustable in length for ease of shipping.